C++ Primer(第五版)学习笔记_4_标准模板库string(1)

标签：c++   stl   

C++ Primer(第五版)学习笔记_4_标准模板库string(1)

1、创建string对象
创建一个空字符串，其长度为0

#include <iostream>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    cout << s.length() << endl;
    return 0;
}

#include <iostream>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s = "hello, C++ STL.";
    cout << s << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s1;
    char ss[5000];
    //scanf的输入速度比cin快的多
    //scanf是C语言的函数，不支持string对象
    scanf("%s", &ss);
    s1 = ss;
    cout << s1 << endl;


    string s2;
    cin >> s2;
    cout << s2 << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s = s + 'a';
    s = s + 'b';
    s = s + 'c';
    cout << s << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s = s + "abc";
    s = s + "123";
    cout << s << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s.append("abc");
    s.append("123");
    cout << s << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s = "123456";
    s.insert(s.begin() + 1, 'p');
    cout << s << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s = "abc123456";
    cout << s[0] << endl;
    cout << s[0] - 'a' << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s = "abc123456";
    //删除第3个元素，元素位置从0开始计数
    s.erase(s.begin() + 3);
    cout << s << endl;
    //删除0~4左闭右开区间的所有元素，[0, 4)
    s.erase(s.begin(), s.begin() + 4);
    cout << s << endl;
    s = "";
    cout << s.length() << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s = "abc123456";
    cout << s.length() << endl;
    cout << s.size() << endl;
    s.clear();
    cout << s.empty() << endl;
    return 0;
}

#include <iostream>
#include <stdio.h>
#include <string>


using namespace std;


int main(int argc, char* argv[])
{
    string s;
    s = "abc123456";
    //从第3个开始，将连续的3个字符替换为"good"
    //即将"1234"替换为good
    s.replace(3, 4, "good");
    cout << s << endl;
    return 0;
}

C++ Primer(第五版)学习笔记_4_标准模板库string(1)

标签：c++   stl   

原文地址：http://blog.csdn.net/keyyuanxin/article/details/46815957